It Was Only Finishing What He Started
by DaughterofDionysus
Summary: My take on the Mark of Cain's effect on Dean, some canon divergence in my take on Hell and Purgatory. Rated M for language.


Sam thought the Mark of Cain was changing him. Well that was fucking adorable.

The Mark wasn't changing him, Dean knew that much. It was finishing what had already started, probably the first time he had killed something. On a hunt, when he was eighteen.

It was a werewolf they'd been hunting, just him and dad, Sam had had to stay at the motel room. He was too young, dad said, of course Dean agreed. Somehow he and the werewolf had both ended up alone in the woods, Dean had managed to wrestle it to the ground and plunge the silver knife into its heart, had seen the light fade from its eyes and watched the soul leave its body. He knew most people threw up when they made their first kill, Sam had. But not him, not Dean. There was a beauty in death, an art in killing and Dean had seen it on that day.

Horrified by his thoughts as he watched the creature die, Dean took all that emotion and shoved it far down within himself. Every time he made a kill in the future he would look away, get the job done quickly. And as for that werewolf? He tried to forget that hunt.

When John Winchester died, something became unhinged in Dean, at least for a while.

He got reckless when hunting, living only for the kills he made and the voice in the back of his head constantly telling him to watch out for Sammy. Dean knew he got vicious when delivering the death blows, he knew there was often a look of savage glee on his face at watching the monsters they hunted die, sometimes Sam saw. But he never once mentioned it, only asked how he was handling dad's death.

It had got a little better after that, Dean had managed to shove down that part of himself again, but it was bigger for the time he nurtured it and allowed it to control him.

Then Sam had died and Dean had thought that he was going to die he hurt so badly. So, he had made the crossroads deal: his soul for eternity in exchange for Sam getting his life back.

Knowing he was going to Hell anyway had lead to a sick kind of freedom for Dean, it didn't matter what he did anymore- he was dying whatever happened.

So, yeah, he got even more reckless. He ate more, drank more, fucked more and yeah, he killed more. And yeah, that sick, twisted part of him enjoyed that.

And then, he went to Hell.

He spent _thirty years_ on Alastair's rack, he was tortured, mutilated, humiliated, broken and torn apart only to be built up again at the end of every day, which was just as painful as the reverse process. So then he agreed to Alastair's terms, he got off the rack and tortured souls in his place.

And he liked it. No, like wasn't a strong enough word for the sick joy, the twisted glee. The disgusting euphoria he felt when hearing the screams of the souls on that rack.

Sam thought he had stayed human. He couldn't be more wrong.

The change hadn't been sudden, Dean hadn't just woken up one day and known. No. It had been gradual, almost unnoticeable at first. But then, he had felt it. Alastair had seen it too. He'd congratulated him, given him extra time to work with the souls. Taught him new methods of torture that only a true demon could master.

And then, there had been light.

Blinding, white, healing light. It had gripped his shoulders and hauled him from the pit. It had rebuilt him, piece by piece, his body, mind and soul. When he had first woken in the grave, Dean had known something was different, he had figured it out when Bobby had chucked Holy water in his face.

Dean Winchester may be human, but that wasn't all he was. The darkness inside of him, which had first shown itself when he was eighteen, was a part of him. The demonic side of him that had become one of Hell's most feared torturers, the most gifted pupil of Alastair, the master torturer, was also Dean Winchester. And that was _never_ going away.

He had control of it though. He really did. Dean had carried on like he always had. It took more effort, sure. Sometimes when he lay awake at night he could still hear the cries of the tortured, and some part of him longed to be back down there- returning the pain he had been dealt sevenfold, fine. But he handled it.

However, it is an acknowledged truth in Heaven, Hell, Earth and now Purgatory that Dean Winchester cannot catch a fucking break.

Sam turned into a demon, the very thing Dean was trying to hide from him.

Then he managed to overcome his demonic side, and he can tell that it barely bothers him anymore. Sam got out. Of course he did. Sammy always gets out.

Then, when Dean had thought he'd suffered enough, when he thought there was nothing Heaven and even Hell could throw at him, Sam had died. Again. But this time, it was for good. He was gone. Locked in the cage with Lucifer and Michael. Not to mention Adam.

Dean tries not to think of the youngest Winchester anymore, not when he knows there's nothing can be done to save him.

And he had managed to live an apple pie life. For a year. A whole fucking year. Not one hunt, and not a single kill.

Something changed though. Something always changes. And this time, it was Sam. His baby brother who he'd given up as dead, who he'd _accepted_ as dead, who he had given up hunting for because Dean had promised Sam he would. Yeah, him. He had come back. From the cage itself.

Of course, then it turned out Sam had no fucking soul. (Just a minor oversight, Cas.) And that scared Dean, Hell, it fucking terrified him. Because some part of Dean, the dark part, envied him. How easily he killed, how quickly he lied, how guilt didn't bother him and others were always second because he always came first.

Those were the things Dean had had as a demon, and there were times when he thought maybe it wouldn't be so bad, if he was a demon again, because everything was so simple, so pure.

And then, after everything had been relatively steady (except for Cas playing God, working with Crowley, nearly wiping out mankind and betraying him and Sam). Then Purgatory happened.

The next in a long line of the long series of 'Dean Winchester can't catch a fucking break'.

Except...

For him, Purgatory had been a break. There had been no Sammy to look out for, no Cas to keep reminding him to stay clean, no 'bigger picture', just the thrill of the chase and the joy of the kill. It had been pure.

But there had always been that part of him, at the back of his head, whispering to him 'You need to watch out for Sammy. You have to find Cas.' Over and over again until Dean thought it would drive him crazy. Well, more crazy than he already thought he was.

So, he had allowed Benny to tell him how to get out, how to leave Purgatory.

He had spent a year in Purgatory, hunting and searching, until eventually he had found Cas. Cas had known, he had seen it in Dean's eyes, that he _liked_ Purgatory. He liked the simplicity that he hadn't had in years, the pureness of just hunting- no strings attached and no bigger picture.

But, as soon as Dean had found Cas his loyalty began to take a firmer hold of him and the darker side of him was once again pushed down. This time it took longer though, and a lot more effort.

Then, after containing himself for so long, he had the Mark of Cain and the darkness was taking over. He had already lost control once, torturing Gadreel had taken so much out of him that he hadn't even been able to hold up his own weight and had collapsed next to the unconscious angel, his own mind in a haze.

And now? Now, after the messed up vamp hunt he was sitting at a table in the Bunker, a bottle of whiskey sitting in front of him and a pile of papers he was supposed to be sorting through next to the bottle. At first, Dean had hid the bottles of whiskey from Sam, not wanting him to start asking questions. Now, he didn't bother. Sam could ask all the fucking questions he wanted, it didn't mean Dean had to answer.

All his brother had to know was a means to an end, that was all anyone had to know.

Dean would kill Abaddon. That much he knew was certain to happen. And if something happened to Dean, if he died, if he turned into a Knight of Hell. If something happened, what did it matter?

Sam had effectively disowned him, Cas would be busy with his angel army and wouldn't need Dean. After that there was no one left to even think about caring. Kevin (or his ghost, whatever) was staying with his mom, Garth was living out an apple pie werewolf life, Charlie was in Oz with Dorothy, Lisa and Ben didn't even remember him.

There was no one and Dean Winchester had nothing.

All that was left was to drink and research. Just waiting for three simple words.

"We found Abaddon."

~Fin~


End file.
